c.1300, from Anglo-French boucher, from Old French bochier "butcher, executioner" (12c., Modern French boucher), probably literally "slaughterer of goats," from bouc "male goat," from Frankish *bukk or some other Germanic source (see buck (n.1)) or Celtic *bukkos "he-goat." Figurative sense of "brutal murderer" is attested from 1520s. Butcher-knife attested from 18c. Related: Butcherly.